src/net_setup.c

   1 /*
   2     net_setup.c -- Setup.
   3     Copyright (C) 1998-2002 Ivo Timmermans <itimmermans@bigfoot.com>,
   4                   2000-2002 Guus Sliepen <guus@sliepen.warande.net>
   5
   6     This program is free software; you can redistribute it and/or modify
   7     it under the terms of the GNU General Public License as published by
   8     the Free Software Foundation; either version 2 of the License, or
   9     (at your option) any later version.
  10
  11     This program is distributed in the hope that it will be useful,
  12     but WITHOUT ANY WARRANTY; without even the implied warranty of
  13     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14     GNU General Public License for more details.
  15
  16     You should have received a copy of the GNU General Public License
  17     along with this program; if not, write to the Free Software
  18     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  19
  20     $Id: net_setup.c,v 1.1.2.17 2002/06/08 12:57:10 guus Exp $
  21 */
  22
  23 #include "config.h"
  24
  25 #include <errno.h>
  26 #include <fcntl.h>
  27 #include <netdb.h>
  28 #include <netinet/in.h>
  29 #ifdef HAVE_NETINET_IP_H
  30  #include <netinet/ip.h>
  31 #endif
  32 #ifdef HAVE_NETINET_TCP_H
  33  #include <netinet/tcp.h>
  34 #endif
  35 #include <stdio.h>
  36 #include <stdlib.h>
  37 #include <string.h>
  38 #include <signal.h>
  39 #include <sys/time.h>
  40 #include <sys/types.h>
  41 #include <syslog.h>
  42 #include <unistd.h>
  43 #include <sys/ioctl.h>
  44 /* SunOS really wants sys/socket.h BEFORE net/if.h,
  45    and FreeBSD wants these lines below the rest. */
  46 #include <arpa/inet.h>
  47 #include <sys/socket.h>
  48 #include <net/if.h>
  49
  50 #include <openssl/pem.h>
  51 #include <openssl/rsa.h>
  52 #include <openssl/rand.h>
  53
  54 #include <utils.h>
  55 #include <xalloc.h>
  56 #include <avl_tree.h>
  57 #include <list.h>
  58
  59 #include "conf.h"
  60 #include "connection.h"
  61 #include "meta.h"
  62 #include "net.h"
  63 #include "netutl.h"
  64 #include "process.h"
  65 #include "protocol.h"
  66 #include "subnet.h"
  67 #include "graph.h"
  68 #include "process.h"
  69 #include "route.h"
  70 #include "device.h"
  71 #include "event.h"
  72
  73 #include "system.h"
  74
  75 char *myport;
  76
  77 int read_rsa_public_key(connection_t *c)
  78 {
  79   FILE *fp;
  80   char *fname;
  81   char *key;
  82 cp
  83   if(!c->rsa_key)
  84     c->rsa_key = RSA_new();
  85
  86   /* First, check for simple PublicKey statement */
  87
  88   if(get_config_string(lookup_config(c->config_tree, "PublicKey"), &key))
  89     {
  90       BN_hex2bn(&c->rsa_key->n, key);
  91       BN_hex2bn(&c->rsa_key->e, "FFFF");
  92       free(key);
  93       return 0;
  94     }
  95
  96   /* Else, check for PublicKeyFile statement and read it */
  97
  98   if(get_config_string(lookup_config(c->config_tree, "PublicKeyFile"), &fname))
  99     {
 100       if(is_safe_path(fname))
 101         {
 102           if((fp = fopen(fname, "r")) == NULL)
 103             {
 104               syslog(LOG_ERR, _("Error reading RSA public key file `%s': %s"),
 105                      fname, strerror(errno));
 106               free(fname);
 107               return -1;
 108             }
 109           free(fname);
 110           c->rsa_key = PEM_read_RSAPublicKey(fp, &c->rsa_key, NULL, NULL);
 111           fclose(fp);
 112           if(c->rsa_key)
 113             return 0; /* Woohoo. */
 114
 115           /* If it fails, try PEM_read_RSA_PUBKEY. */
 116           if((fp = fopen(fname, "r")) == NULL)
 117             {
 118               syslog(LOG_ERR, _("Error reading RSA public key file `%s': %s"),
 119                      fname, strerror(errno));
 120               free(fname);
 121               return -1;
 122             }
 123           free(fname);
 124           c->rsa_key = PEM_read_RSA_PUBKEY(fp, &c->rsa_key, NULL, NULL);
 125           fclose(fp);
 126           if(c->rsa_key)
 127             return 0;
 128
 129           syslog(LOG_ERR, _("Reading RSA public key file `%s' failed: %s"),
 130                  fname, strerror(errno));
 131           return -1;
 132         }
 133       else
 134         {
 135           free(fname);
 136           return -1;
 137         }
 138     }
 139
 140   /* Else, check if a harnessed public key is in the config file */
 141
 142   asprintf(&fname, "%s/hosts/%s", confbase, c->name);
 143   if((fp = fopen(fname, "r")))
 144     {
 145       c->rsa_key = PEM_read_RSAPublicKey(fp, &c->rsa_key, NULL, NULL);
 146       fclose(fp);
 147     }
 148
 149   free(fname);
 150
 151   if(c->rsa_key)
 152     return 0;
 153
 154   /* Try again with PEM_read_RSA_PUBKEY. */
 155
 156   asprintf(&fname, "%s/hosts/%s", confbase, c->name);
 157   if((fp = fopen(fname, "r")))
 158     {
 159       c->rsa_key = PEM_read_RSA_PUBKEY(fp, &c->rsa_key, NULL, NULL);
 160       fclose(fp);
 161     }
 162
 163   free(fname);
 164
 165   if(c->rsa_key)
 166     return 0;
 167
 168   syslog(LOG_ERR, _("No public key for %s specified!"), c->name);
 169   return -1;
 170 }
 171
 172 int read_rsa_private_key(void)
 173 {
 174   FILE *fp;
 175   char *fname, *key;
 176 cp
 177   if(get_config_string(lookup_config(config_tree, "PrivateKey"), &key))
 178     {
 179       myself->connection->rsa_key = RSA_new();
 180       BN_hex2bn(&myself->connection->rsa_key->d, key);
 181       BN_hex2bn(&myself->connection->rsa_key->e, "FFFF");
 182       free(key);
 183       return 0;
 184     }
 185
 186   if(!get_config_string(lookup_config(config_tree, "PrivateKeyFile"), &fname))
 187     asprintf(&fname, "%s/rsa_key.priv", confbase);
 188
 189   if(is_safe_path(fname))
 190     {
 191       if((fp = fopen(fname, "r")) == NULL)
 192         {
 193           syslog(LOG_ERR, _("Error reading RSA private key file `%s': %s"),
 194                  fname, strerror(errno));
 195           free(fname);
 196           return -1;
 197         }
 198       free(fname);
 199       myself->connection->rsa_key = PEM_read_RSAPrivateKey(fp, NULL, NULL, NULL);
 200       fclose(fp);
 201       if(!myself->connection->rsa_key)
 202         {
 203           syslog(LOG_ERR, _("Reading RSA private key file `%s' failed: %s"),
 204                  fname, strerror(errno));
 205           return -1;
 206         }
 207       return 0;
 208     }
 209
 210   free(fname);
 211   return -1;
 212 }
 213
 214 /*
 215   Configure node_t myself and set up the local sockets (listen only)
 216 */
 217 int setup_myself(void)
 218 {
 219   config_t *cfg;
 220   subnet_t *subnet;
 221   char *name, *hostname, *mode, *afname, *cipher, *digest;
 222   char *address = NULL;
 223   struct addrinfo hint, *ai, *aip;
 224   int choice, err;
 225 cp
 226   myself = new_node();
 227   myself->connection = new_connection();
 228   init_configuration(&myself->connection->config_tree);
 229
 230   asprintf(&myself->hostname, _("MYSELF"));
 231   asprintf(&myself->connection->hostname, _("MYSELF"));
 232
 233   myself->connection->options = 0;
 234   myself->connection->protocol_version = PROT_CURRENT;
 235
 236   if(!get_config_string(lookup_config(config_tree, "Name"), &name)) /* Not acceptable */
 237     {
 238       syslog(LOG_ERR, _("Name for tinc daemon required!"));
 239       return -1;
 240     }
 241
 242   if(check_id(name))
 243     {
 244       syslog(LOG_ERR, _("Invalid name for myself!"));
 245       free(name);
 246       return -1;
 247     }
 248
 249   myself->name = name;
 250   myself->connection->name = xstrdup(name);
 251
 252 cp
 253   if(read_rsa_private_key())
 254     return -1;
 255
 256   if(read_connection_config(myself->connection))
 257     {
 258       syslog(LOG_ERR, _("Cannot open host configuration file for myself!"));
 259       return -1;
 260     }
 261
 262   if(read_rsa_public_key(myself->connection))
 263     return -1;
 264 cp
 265
 266   if(!get_config_string(lookup_config(myself->connection->config_tree, "Port"), &myport))
 267     asprintf(&myport, "655");
 268
 269 /* Read in all the subnets specified in the host configuration file */
 270
 271   cfg = lookup_config(myself->connection->config_tree, "Subnet");
 272
 273   while(cfg)
 274     {
 275       if(!get_config_subnet(cfg, &subnet))
 276         return -1;
 277
 278       subnet_add(myself, subnet);
 279
 280       cfg = lookup_config_next(myself->connection->config_tree, cfg);
 281     }
 282
 283 cp
 284   /* Check some options */
 285
 286   if(get_config_bool(lookup_config(config_tree, "IndirectData"), &choice))
 287     if(choice)
 288       myself->options |= OPTION_INDIRECT;
 289
 290   if(get_config_bool(lookup_config(config_tree, "TCPOnly"), &choice))
 291     if(choice)
 292       myself->options |= OPTION_TCPONLY;
 293
 294   if(get_config_bool(lookup_config(myself->connection->config_tree, "IndirectData"), &choice))
 295     if(choice)
 296       myself->options |= OPTION_INDIRECT;
 297
 298   if(get_config_bool(lookup_config(myself->connection->config_tree, "TCPOnly"), &choice))
 299     if(choice)
 300       myself->options |= OPTION_TCPONLY;
 301
 302   if(myself->options & OPTION_TCPONLY)
 303     myself->options |= OPTION_INDIRECT;
 304
 305   if(get_config_string(lookup_config(config_tree, "Mode"), &mode))
 306     {
 307       if(!strcasecmp(mode, "router"))
 308         routing_mode = RMODE_ROUTER;
 309       else if (!strcasecmp(mode, "switch"))
 310         routing_mode = RMODE_SWITCH;
 311       else if (!strcasecmp(mode, "hub"))
 312         routing_mode = RMODE_HUB;
 313       else
 314         {
 315           syslog(LOG_ERR, _("Invalid routing mode!"));
 316           return -1;
 317         }
 318       free(mode);
 319     }
 320   else
 321     routing_mode = RMODE_ROUTER;
 322
 323   get_config_bool(lookup_config(config_tree, "PriorityInheritance"), &priorityinheritance);
 324 #if !defined(SOL_IP) || !defined(IP_TOS)
 325   if(priorityinheritance)
 326     syslog(LOG_WARNING, _("PriorityInheritance not supported on this platform"));
 327 #endif
 328
 329   if(!get_config_int(lookup_config(config_tree, "MACExpire"), &macexpire))
 330     macexpire= 600;
 331
 332   if(get_config_int(lookup_config(myself->connection->config_tree, "MaxTimeout"), &maxtimeout))
 333     {
 334       if(maxtimeout <= 0)
 335         {
 336           syslog(LOG_ERR, _("Bogus maximum timeout!"));
 337           return -1;
 338         }
 339     }
 340   else
 341     maxtimeout = 900;
 342
 343   if(get_config_string(lookup_config(config_tree, "AddressFamily"), &afname))
 344     {
 345       if(!strcasecmp(afname, "IPv4"))
 346         addressfamily = AF_INET;
 347       else if (!strcasecmp(afname, "IPv6"))
 348         addressfamily = AF_INET6;
 349       else if (!strcasecmp(afname, "any"))
 350         addressfamily = AF_UNSPEC;
 351       else
 352         {
 353           syslog(LOG_ERR, _("Invalid address family!"));
 354           return -1;
 355         }
 356       free(afname);
 357     }
 358   else
 359     addressfamily = AF_INET;
 360
 361   get_config_bool(lookup_config(config_tree, "Hostnames"), &hostnames);
 362 cp
 363   /* Generate packet encryption key */
 364
 365   if(get_config_string(lookup_config(myself->connection->config_tree, "Cipher"), &cipher))
 366     {
 367       if(!strcasecmp(cipher, "none"))
 368         {
 369           myself->cipher = NULL;
 370         }
 371       else
 372         {
 373           if(!(myself->cipher = EVP_get_cipherbyname(cipher)))
 374             {
 375               syslog(LOG_ERR, _("Unrecognized cipher type!"));
 376               return -1;
 377             }
 378         }
 379     }
 380   else
 381     myself->cipher = EVP_bf_cbc();
 382
 383   if(myself->cipher)
 384     myself->keylength = myself->cipher->key_len + myself->cipher->iv_len;
 385   else
 386     myself->keylength = 1;
 387
 388   myself->connection->outcipher = EVP_bf_ofb();
 389
 390   myself->key = (char *)xmalloc(myself->keylength);
 391   RAND_pseudo_bytes(myself->key, myself->keylength);
 392
 393   if(!get_config_int(lookup_config(config_tree, "KeyExpire"), &keylifetime))
 394     keylifetime = 3600;
 395
 396   keyexpires = now + keylifetime;
 397
 398   /* Check if we want to use message authentication codes... */
 399
 400   if(get_config_string(lookup_config(myself->connection->config_tree, "Digest"), &digest))
 401     {
 402       if(!strcasecmp(digest, "none"))
 403         {
 404           myself->digest = NULL;
 405         }
 406       else
 407         {
 408           if(!(myself->digest = EVP_get_digestbyname(digest)))
 409             {
 410               syslog(LOG_ERR, _("Unrecognized digest type!"));
 411               return -1;
 412             }
 413         }
 414     }
 415   else
 416     myself->digest = EVP_sha1();
 417
 418   myself->connection->outdigest = EVP_sha1();
 419
 420   if(get_config_int(lookup_config(myself->connection->config_tree, "MACLength"), &myself->maclength))
 421     {
 422       if(myself->digest)
 423         {
 424           if(myself->maclength > myself->digest->md_size)
 425             {
 426               syslog(LOG_ERR, _("MAC length exceeds size of digest!"));
 427               return -1;
 428             }
 429           else if (myself->maclength < 0)
 430             {
 431               syslog(LOG_ERR, _("Bogus MAC length!"));
 432               return -1;
 433             }
 434         }
 435     }
 436   else
 437     myself->maclength = 4;
 438
 439   myself->connection->outmaclength = 0;
 440
 441   /* Compression */
 442
 443   if(get_config_int(lookup_config(myself->connection->config_tree, "Compression"), &myself->compression))
 444     {
 445       if(myself->compression < 0 || myself->compression > 9)
 446         {
 447           syslog(LOG_ERR, _("Bogus compression level!"));
 448           return -1;
 449         }
 450     }
 451   else
 452     myself->compression = 0;
 453
 454   myself->connection->outcompression = 0;
 455 cp
 456   /* Done */
 457
 458   myself->nexthop = myself;
 459   myself->via = myself;
 460   myself->status.active = 1;
 461   myself->status.reachable = 1;
 462   node_add(myself);
 463
 464   graph();
 465
 466 cp
 467   /* Open sockets */
 468
 469   memset(&hint, 0, sizeof(hint));
 470
 471   get_config_string(lookup_config(config_tree, "BindToAddress"), &address);
 472
 473   hint.ai_family = addressfamily;
 474   hint.ai_socktype = SOCK_STREAM;
 475   hint.ai_protocol = IPPROTO_TCP;
 476   hint.ai_flags = AI_PASSIVE;
 477
 478   if((err = getaddrinfo(address, myport, &hint, &ai)) || !ai)
 479     {
 480       syslog(LOG_ERR, _("System call `%s' failed: %s"), "getaddrinfo", gai_strerror(err));
 481       return -1;
 482     }
 483
 484   for(aip = ai; aip; aip = aip->ai_next)
 485     {
 486       if((listen_socket[listen_sockets].tcp = setup_listen_socket((sockaddr_t *)aip->ai_addr)) < 0)
 487         continue;
 488
 489       if((listen_socket[listen_sockets].udp = setup_vpn_in_socket((sockaddr_t *)aip->ai_addr)) < 0)
 490         continue;
 491
 492       if(debug_lvl >= DEBUG_CONNECTIONS)
 493         {
 494           hostname = sockaddr2hostname((sockaddr_t *)aip->ai_addr);
 495           syslog(LOG_NOTICE, _("Listening on %s"), hostname);
 496           free(hostname);
 497         }
 498
 499       listen_socket[listen_sockets].sa.sa = *aip->ai_addr;
 500       listen_sockets++;
 501     }
 502
 503   freeaddrinfo(ai);
 504
 505   if(listen_sockets)
 506     syslog(LOG_NOTICE, _("Ready"));
 507   else
 508     {
 509       syslog(LOG_ERR, _("Unable to create any listening socket!"));
 510       return -1;
 511     }
 512 cp
 513   return 0;
 514 }
 515
 516 /*
 517   setup all initial network connections
 518 */
 519 int setup_network_connections(void)
 520 {
 521 cp
 522   now = time(NULL);
 523
 524   init_connections();
 525   init_subnets();
 526   init_nodes();
 527   init_edges();
 528   init_events();
 529   init_requests();
 530
 531   if(get_config_int(lookup_config(config_tree, "PingTimeout"), &pingtimeout))
 532     {
 533       if(pingtimeout < 1)
 534         {
 535           pingtimeout = 86400;
 536         }
 537     }
 538   else
 539     pingtimeout = 60;
 540
 541   if(setup_device() < 0)
 542     return -1;
 543
 544   /* Run tinc-up script to further initialize the tap interface */
 545   execute_script("tinc-up");
 546
 547   if(setup_myself() < 0)
 548     return -1;
 549
 550   try_outgoing_connections();
 551 cp
 552   return 0;
 553 }
 554
 555 /*
 556   close all open network connections
 557 */
 558 void close_network_connections(void)
 559 {
 560   avl_node_t *node, *next;
 561   connection_t *c;
 562   int i;
 563 cp
 564   for(node = connection_tree->head; node; node = next)
 565     {
 566       next = node->next;
 567       c = (connection_t *)node->data;
 568       if(c->outgoing)
 569         free(c->outgoing->name), free(c->outgoing), c->outgoing = NULL;
 570       terminate_connection(c, 0);
 571     }
 572
 573   if(myself && myself->connection)
 574     terminate_connection(myself->connection, 0);
 575
 576   for(i = 0; i < listen_sockets; i++)
 577     {
 578       close(listen_socket[i].tcp);
 579       close(listen_socket[i].udp);
 580     }
 581
 582   exit_requests();
 583   exit_events();
 584   exit_edges();
 585   exit_subnets();
 586   exit_nodes();
 587   exit_connections();
 588
 589   execute_script("tinc-down");
 590
 591   close_device();
 592 cp
 593   return;
 594 }